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根据凝固模型计算的补缩距离,将有助于铸件冒口位置的确定。计算了带有冒口的二维铸扳的凝固模型描绘沿铸扳中心线凝固和收缩情况的所谓的凝固图。当中心线上的毛细管长度大于毛细作用的补缩距离时,缩松就必然出现。有可能用这种方法来确定一些纯金属、共晶型合金和具有窄凝固区间的合金的最大补缩范围。简化了的计算毛细作用补缩距离的方程是以铸钢用石英砂型铸造的试验数据为基础,然后用于其它的金属及合金。正如所料,铸铁的补缩距离主要决定于凝固时的收缩。铝及近共晶铝硅合金的计算结果与试验数据的一致性很好。铜及一些窄凝固范围的铜合金的计算结果恰在文献所列数据的范围以内。对于宽凝固范围的合金,大量补缩停止后进行的枝晶间补缩,亦可以进行计算。对一些合金的显微缩松的数据和分布,计算结果看来与文献所载的试验资料完全一致,但缩孔仍在很大程度上还取决于气体的含量。
According to the solidification model calculation of the retraction distance, will help determine the position of casting riser. The solidification model of a two-dimensional cast plate with a riser was calculated as a so-called solidification diagram depicting solidification and shrinkage along the centerline of the cast plate. When the capillary length of the center line is greater than the capillary action of the shrinkage distance, shrinkage will inevitably occur. It is possible to use this method to determine the maximum fill range for some pure metals, eutectic alloys and alloys with narrow solidification intervals. The simplified equations for calculating the wicking distance are based on experimental data on the casting of quartz sand foundry cast steel and are then used on other metals and alloys. As expected, the makeup distance of cast iron is mainly determined by the shrinkage during solidification. The calculated results of aluminum and near-eutectic Al-Si alloys are in good agreement with the experimental data. Copper and some narrow solidification range of copper alloy calculation results just within the range of the data listed in the literature. For a wide range of solidification alloy, a large number of replenishment stops after the interdendritic shrinkage can also be calculated. The data and distribution of the micro-shrinkage of some alloys appears to be in good agreement with the experimental data contained in the literature, but the shrinkage is still largely dependent on the gas content.